Software testing is an ongoing task in computer software program development and maintenance which requires a large portion of development time, computer and human resources, and effort. Software development may include the development of an entirely new application or program, or the addition of a new feature to an existing application. Software maintenance activities generally include the correction of reported problems.
Testing is performed with the goal of verifying the correct functioning of new software and modifications to existing software. Generally, software testing accompanies even minor code modifications or enhancements to ensure correctness. Verifying the correctness of software may involve numerous tasks ranging from ensuring correct coding syntax through successful compilation, to checking the execution results by examining the output of a software program.
In order to test the execution of software, a machine-executable program comprising binary instructions and data in machine-readable form must be produced and executed. The software may be written in some high-level or low-level programming language. This software may be processed by a compiler, language processor, or translator to produce an object file containing binary or machine-readable code. Usually, there are multiple software modules or source files (herein generically referred to as software components) which comprise the software to be tested. Each of these software modules may be separately compiled, and a separate object file may be produced for each of these source files. These object files may be combined into a single machine-executable program using an operating system tool such as a linker which links together the multiple object files containing binary code and data to produce a single combined machine-executable program containing binary code and data. This machine-readable program may be run or executed on a computer system, and the results from the execution may be examined as a means to ensure correct functioning of the software.
Software programs vary in complexity and size. Both the small and simple programs as well as the large and more complex programs have a need for efficient software testing. Generally, as complexity and size increase, the amount of testing and the need for efficient testing increases as well.
For example, if the goal is to test a complex software component (such as a “cluster operating system”) as a black box, two problems are immediately faced. First, there will be an enormous number of test cases based on the number of potential inputs (i.e., the software is multi input and multi exit), without necessarily validating the validity of the individual tests. In addition, a large amount of time will be required in order to execute all of the tests needed to verify the complex software component.
In view of this, the present invention is directed in a general aspect to enhanced methods and apparatus for testing and evaluating software, and more particularly, to enhanced techniques for efficiently testing and evaluating a complex software component in order to minimize the number of test cases required to validate the software component and reduce overall time required to execute the test cases.